Blank-holding and clutch-operating mechanism for presses



y 7, 1930. B. J. LINDGREN 1,760,151

BLANK HOLDING AND CLUTCH OPERATING MECHANISM FOR PRESSES Filed Aug. 24, 1926 5 Sheets-Sheet 1 fizz/67156 {idm May 27, 1930. B. J. LINDGREN 1,760,151

BLANK HOLDING AND CLUTCH OPERATING MECHANISM FOR PRESSES Fi led Aug. 24. 1926 5 Sheets-Sheet 2 May 27, 1930.

Filed Aug. 24, 1926 B. J. LINDGREN BLANK HOLDING AND CLUTCH OPERATING MECHANISM FOR PRESSES 5 Sheets-Sheet 3 y 1930. B. J. LINDGREN 1,760,151

BLANK HOLDING AND CLUTCH OPERATING MECHANISM FOR PRESSES Filed Au 24. 1926' 5 Sheets-Sheet 4 y 1930. B. J. LINDGREN 1,760,151

BLANK HOLDING AND GLUTCH'OPERATING MECHANISM FOR PRESSES Filed Aug. 24, 1926 I 5 Sheets-Sheet 5 2.5 /40 1| 5 M I HI 2 45 98 v O W! Patented May 27, 1930 UNITED STATE-S PATENT OFFICE amorar.r.mnennn, or BUFFALO, unwvonk, Assreuon "r NIAGARA macnnvn & 'roor.

' WORKS, OFBUFFALO, -NEW FORK, A

CORPORATION OF NEW YORK BLANK-HOLDING CLUTCH-OPERATING MECHANISM FOR PBESSES Application filed August 24, 1926. Serial No. 131,221.v

This invention relates to a press which is more particularly designed for drawing sheet metal'into various shapes and more particularly to the means for holding the sheet of metal while the same is being drawn and the mechanism for controlling the operation of the clutch which connects and disconnect-s the press with the driving shaft.

, One of the objects of this invention 'is to provide improved means for holdin the sheet metal blank while the same is eing drawn which means operate quickly and effectively hold the blank with .a] powerful rip and prevent the same from becoming isplaced while being operated upon.

Another object of this invention is to provide improved means for causing the clutch to be started by manual power and to be stopped automatically at the end of each cycleof operations which means are quick in action and operate to start and stop the press romptly;

' In t e accompanying drawings Figure 1 is a front elevation of a draw 2 press embodying my improvements showing occupy the'parts in the position which the eld and when sheet metal blank is being drawn. g

Figure 2 is a fragmentary elevation of the same viewed from the left hand side. Figure 3 is a fragmentary elevation of the same viewed from the right hand side an showing a part thereof'broken out and shown in section on line 3-3, Figure 1.

Figure 4 is a fragmentary elevationof the press viewed from the left hand side thereof showing the upper holding die and formingtool in the elevated inoperative position' Figure 5-is .a vertical section of the press taken on line 5-5 showing the parts in the position corresponding to Figure 4:.

- Figure-6 is a horizontal section taken on line 6-6, Figure 1.

Figure 7 is a fragmentary front elevation of the press showing the driving clutch in an open or uncoupled position an parts of the clutch operating mechanism in section.

Figure 8 is a fragmentary vertical section taken on line 8-8, Figure -7.

Figure 9 is a fragmentary vertical-section (1 top of the taken on line 9-9, Figure 7, showing parts of the clutch operating parts in the position which they occupy when the press is at rest.

Flgure 10 is a view similar to Figure 7 but showing the position of the parts when the clutch operating mechanism has been tripped by foot pressure and the clutch is closed to couple the holding Figure ll is a view similar to Figure 9', but showing the clutch operating mechanism locked for safety when adjusting the dies and tools and getting the press ready. Y

Figure 12 is a fragmentary perspective View of the clutch operating mechanism.

Similar characters of reference indicate like partsin the several figures of the drawmgs.

'lhe main frame of this. press is of usual construction and comprises a base having a driving shaft with the upper! die and upper forming tool 'operat1ng mechanism.

bed or table 20 provided with supporting legs 21, standards 22, 23 rising from said bed,- and a head 24 connecting the upper ends of said standards. Upon the bed is arranged the lower holding and drawing die forming part of the means for holding and drawing the sheet metal blank 25. Thislower die in the present instance comprises an upri ht tubularbody 26 provided at its lower e ge with a flange 27 secured to the and drawing die'is arranged an upper holding die 28 which moves vertically toward and from the upper end of the lower holding die betwe'em and an upper drawing die or form- 7 ing tool .29 which is movable vertically through an opening 30 inthe upper holding die and adapted to push the adjacent part of the'sheet metal blank downwardly into the bore of. the lower die the requisite extent to suit the draw desired.

The upper holding die isrmounted on the under side of. a vertically movable outer slide or cross head 31 which is guided on the inner side of the standards and the upper vertically movable inner slide or cross head 32 which is guided on the outer slide 31. I

bed. Above the lower holding for gripping the sheet metal theredrawing die or forming tool is mounted on a The numeral 33 represents the main driving shaft of the press which is mounted horizontally and lengthwise in suitable bearings on the lower rear part of the standards and provided with a fly wheel 34 and with tight and loose pulleys 35, 36, adapted to receive a driving belt. Above the die is arranged a crank shaft 37 which is journaled horizonlengthwise on the driving shaft and adapted tally and lengthwise in suitable bearingsin the upper parts of the standards and provided between thesame with a main crank 38 which is connected by a connectingrod or pitman 39 with the inner slide 32. At one end the crank shaft is provided with a large gear wheel 40 which meshes with a small gear wheel or pinion 41 on the main driving shaft.

This pinion is adapted to. be connected with to couple and uncouple the friction plates to transmit motion from the driving shaft to the crank shaft or to interrupt the transmission of such motion. I r

The means whereby motion is transmitted from the crank shaft to the upper holding die and which contain some of the features of my invention are constructed as follows:

The numerals 46, 46, represent two trans verse operating bars arranged above the outer slide and on opposite sides of the pitman and each adjustably connected on its] under side with the adjacent part of the outer slide 31 by means of upright adjusting rods 47.

Above those operating barsand on opposite sides of the crank shaft arranged front and rear lower rock shafts 48,49 and above the latter are arranged front and rear upper rock shafts 50, 51, those several rock shafts being arranged horizontally and lengthwise of the press and journaled in suitablebearings on the upper partsof the frame standards, as shown in Figures 1-6; v t The front lower rock shaft 48 is provided with two lower rock arms 52 which are connected respectively by links 53 with the front ends of the operating bars 46 and practically form toggles therewith, andthe rear lower rock shaft 49 is also provided with two lower rock arms 54 which are connected re ectively by links 55 with. the rear ends of said ing bars.

The front and rear lower rock shafts are also provided respectively with upper rock arms 56, 57 The front and rear upper'rock shafts 50, 51 are provided respectively with lower rock arms 58,59 and on the left hand operat-"T I the upper holding die reachesthe limit of the downward motion, the toggle members of the v spectively, with upper rock arms 60, 61 which are arranged outside of the adjacent standard. J be lower arm 58 of the upper front rock shaft 50 is connected by a link 62 with the up per rock arm 57 of the lower rear rock shaft .49, and the lowerarm 59 of the upper rear rock shaft 51 is connected by a link 63. The

links 62 and 63 and the arms associated therewith are arranged in different planes in a direction lengthwise of the rock shafts to permit these links to. shown in Figure 6.

' On the outer. side of the left hand standard is arranged a vertically movable toggle slide 64 which is guided on an upright bar 65 mounted at its opposite ends on the adjacentstandard. At its upper'end this toggle slide is connected by with the outer rock arms 60, 61 of the upper front and rear rock shafts 50, 51', and the lower end of this slide is connected by a link 68 with an auxiliary crank arm, 69 at the left hand end of the crank shaft 37 outside of the 7 adjacent standard, as shown in Figure The several parts just described are so timed and organized that when the crank shafts start to rotate its outer'crank69 operpass each other, as best front and rear links 66, 67,

ates to raise the toggle slide 64 and the latter turns the upper rock shafts 50, 51 through the medium of the links 66, 67 and rock arms 60, '61. These shafts in turn rotate the lower rock shafts 48 49, through the medium of the links 62, 63 and arms 57, 58, 56, 59. Motion is then transmitted from the lower rock shafts 48,49 by the arms 52, 54 and links 53, 55 to the slide 31 carrying the upper holding die 28 so that the latter is 'moved downwardly in advance ofthe upper drawing tool 29 and causes. the sheet metal blank to be gripped between the upper and lower holding dies and prevent the same from slipping upon being engaged immediately thereafter by the upper drawing tool 29. v a

It will be noted that in this holding mechanism the upper holding die is pressed toward the lower holding die by three sets of toggle very powerful clamping action on thesheet 'metal is thus obtained which positively prevents displacementof the same and insures proper drawing of the same when engaged by the upper drawing tool. The several sets of toggle members are so arranged that when set between the toggle slide andthe lower rc 3k shafts will be passing dead centers, as shown in Figures 2 and 3, and the links 62 and 63 will also be passing dead cen ters relw members, one 'set of which is interposed rate. v i

Clutch controlling means are provided whereby the clutch hereinbefore' mentioned may be operated easily, quickly and reliably so that it can be started promptly by manual power and stopped automatically at the end of each cycle of operations. In its preferred form, this clutch operating mechanism is constructedas follows:

The numeral 70 represents a horizontal shipper rod which isarranged lengthwise below the clutch and guided by a bracket 71 forming part of the main frame. This shipper rod is provided with a forked arm 72 which engages the shifting sleeve of the clutch so as to be compelled to move lengthwise therewith but permits the sleeve to turn independently of said forked arm.

Jonrnaled transversely in the lower part .of the bracket 71 is a horizontal rpck shaft 7 3 provided with a rear arm 7 4 engaging with the shipper rod and front trip arm75 which is adapted to be operated either manually or automatically. 0n the inner part of the bracket 71 is pivotally mounted a vertically swinging elbow, lever having a lower vertical arm 76 and an upper horizontal arm 77. 'Between the trip arm 7 5 and the lower elbow arm 76 is arranged a toggle consisting of two links 78, 79 connected with each other at their opposing ends by a pivot pin 80 while their extremities are pivotally connected re-- spectively, with the trip arm 75 and the lower elbow arm 76. The downward movement of the toggle links 7 8, 79' when the same are 'in a straightened, unfolded or dead center position is limited by a stop. device consisting preferably of aJstop lug 81 arranged on one of these links and engaging with the top of the other link, as shown in Figures 1 and 7. Pivotally mounted on the upper outer part of the right hand standard is a cam lever of elbow form which engages a trip cam on the crank shaft 37, this cam lever in its preferred form having an upper vertical arm 82 which engages a cam section 83 on the crank shaftand a lower rearwardly projecting arm' 84 engaging with a cam section 85 on this shaft, whereby these two cam sections operate like a groove cam for positively rocking the cam lever 82, 84: in opposite directions upon rotating the crank shaft. The lower rearwardlyprojecting arm'84 of this cam lever is connected by a rod 86 with the upper horizontal arm 77 of the intermediate elbow lever.

The toggle, links are folded upwardly by manual power which may be transmitted thereto either by a foot lever or pedal 87 or by a hand lever 88. F or this purpose, this hand lever is mounted on a rock shaft 89 journaled on the lower part of the main frame and provided with an inwardly projecting arm 90 which is connected by an upright rod 91 with. the toggle link 7 9, and the pedal 87 is pivoted on the lower part of the frame-and connected with the rock shaft 89 by an intermediate rock lever 92 pivoted on the frame and :having one of its arms connected by a rod 93 with the pedal while its opposite arm is connected by a rod 94 with the arm 90 on the rock shaft 89. Upon rocking the latter either by foot or hand pressure in the direction for raising the rod 91 the toggle links 78, 79 will be broken or unfolded and cause one of the members with which they are connected to move toward the other.

When the press is at rest the clutch is open or uncoupled and the operating mechanism for the same is in-the position? shown in Figures 7 and 9. In order to couple the clutch for starting the press the attendant raises the trip rod 91 so as to fold or break the toggle formed by the links 78, 79 during which'operation the latter fold upwardly and cause the shipper rod 70 to be moved in- ,wardly so as to couple the clutch, as shown in Figure 10, it being understood that the elbow lever 76,77, at this'time is stationary and forms a fixed anchor or fulcrum for the link 79 and thereby causing an upward movement of these links to positively close the clutch. As the press starts the shipper rod 70 remains in the position in which theclutch is closed or coupled and during the first part 'of the rotationof the cam 83, 85, with the crank shaft thi's'cam turns the cam elbow lever so that its upper arm 82 moves forward-.

ly and its lower arm 84 moves upwardly,

86 and causing the toggle links 7 8', 7 9 to again straighten notwithstanding that the arm 75 andthe shipper rod connected therewith are stationary at this time, as shown in Figure 1,

and the clutch closed.

As the crank shaft approaches the end of therotation and the press is about to complete a cycle of operations, the cam 83, 85

turns the cam lever so that the arm 82 moves backwardly and the arm 84 moves downward- I 1y, thereby causing a depression of the rod 86v which movement is transmitted by the elbow lever 76, 77 and toggle links 78, 79, now. in

a strai htened'condition, to the arms 74, 7 5

and shlpper rod 70 so that the'clutch is un-' coupled, as shown in Figure 7. i

\Means are rovided for rendering inoperative the mec anism whereby the clutch is coupled so' as to prevent. operation. of the 110 thereby producing an upward pull on the rod press when mountingthe dies therein, effect- 7 .mg ad ustment or repairs or any other service which renders it necessary tooperate the machine by hand, stopping and starting the rotation of the crank shaft at will of the operator. 7 The preferred form of locking means for this purpose consists in providing zbolt 97fconnected withthe upper end 9f the the lower arm 8 10f the cam lever with a slot .96 which extends from a point vertically on line with the fulcrum of the cam lever to a P011117 on one side of this line, and a clamping rod 86 and arranged in the slot 96. When the press 1s in operation the shifting rod is connected with the extremity of the lower arm of the cam lever, as shown in Figure 9, but when it is desired to operate the press by hand, the clamping bolt 97 is shifted to the inner end of the slot 96, so that the shifting rod 86 is in line with the fulcrum of the cam lever, as shown in Figure 11, at which time the turning of the crank shaft is under con trol of the operator, for setting dies.

When'the press completes a cycle of operations is should be stopped as quickly as possible and to do this promptly means are provided which in their preferred form are constructed as follows The numerals 98, 98, represent two brake shoes adapted to engage opposite sides of the brake drum 43 and mounted on the upper arms of brake levers 99 which are pivoted on a lateral extension of the bracket 7 1. Between theserbrake levers is arranged an elbow operating lever which is pivotally' mounted onfl this bracket and has an up- I wardlyfprojecting arm 100 which-connects .positely extending toggle links 102.- Whenf the clutch is closed or coupled the-operating with the shipper rod 70 and ahorizontally extending 'arm 101 which has its free end.

arranged between the lower arms of the brake levers and connected therewith by oplever'lOO, 101, is turned by the shipper rod so as to depress the inner ends of the toggle links 102 to a considerable extent, as shown in Figure 3, whereby the brakelevers are turned so as to disengage the brake shoes I from the drum 43 and permit the press to run 1 so freely. When the shipper rod is moved in the direction for uncouplingor-opening the clutch the operating lever 100, 101, is turned in the opposite direction and raises the inner ends of the toggle links 102 so as to spread the lower arms of the brake levers and cause the brake shoes to be pressed against-opposite sides of the brake drum and thereby stop the operation ofthe press quickly.

By means of the herein described improveirients, the press can be operated very rapidly and brought'quickly to a stop and the sheet metal blanks are also held very firmly while bein drawn, thereby enabling I claim as my invention f- 1. A press comprising a holding die slide, front and rear rock shafts each having lower rock arms and an upper rock arm, links connecting the lower arrnsw of said lower shafts with said holding die slide, front and rear upper rock shafts arranged above said front and rear lower shafts and each having a lower rock arm and an upper rock arm, a link connecting the lower arm of said front upper rock shaft with the upper arm of said lower rear rock shaft-and another link connecting the lower arm of the upper rear rock shaft with the'up'per arm of the lower front rock" shaft, and means for actuating the upper arms of said upper rock shafts.

2. A press comprisin a holding die slide,

front and rear rock sha ts each having lower rock armsand an upper rock arm, links connecting the lower arms of said lower shafts with said holding die slide, front and rear upper rock shafts arranged above said front and rear lower shafts and each having a lower rack arm and an upper rock arm, a link connecting the lower arm of said front upper rock shaft with the upperarm of said lower rear rock shaft and another link con- I necting the lower arm of the upper rear rock shaftwith the upper arin of the lower front rock shaft, a vertically movable toggle slide,

and links connecting said toggle slide with the upper rock arms of said upper rock shafts.

3. A press comprisin front and rear rock shafts each having lower rock arms and an upper rock arm, links cona holding die slide,

necting the lowerarms of said lower shafts Y i with said holding die slide, front and rear upper rock shafts arranged'above said front and rear lower shafts and each having a lower rock arm and an upper rock arm, a link tool and an auxiliary crank, and a link for connecting said auxiliary crank with 'said toggle slide. v

In testimony whereof I hereby affix my signature.

BROR J. LINDGREN.

perfect goods to e produced expeditiously and economically. 

